Virgin Group companies include Virgin Trains, a railroad operator in Britain, and Virgin Galactic, which is dedicated to commercial spaceflight.

Hyperloop One employees do not call their project a train — after all, it does not use tracks. Instead, magnetically levitating passenger pods use electric propulsion to zip through low-pressure tubes, transporting people and cargo at speeds of up to 670 miles per hour. That’s the idea, at least: No human has taken one of these high-speed rides just yet.

But Hyperloop One has been developing the technology for years, applying for dozens of patents and sending one pod on a successful 500-meter test run in July. Now the company is ramping up its business development and fund-raising.

“We would have done the branding deal and the partnership if they didn’t invest a penny,” Marvin Ammori, Hyperloop One’s general counsel, said of Virgin in a phone interview on Thursday. “They have experience taking on incumbent industries with innovation.”

“This feels like the moment when all of this stuff is coming together,” Mr. Ammori said.

High-speed travel in levitating pods is still in its early stages, so Hyperloop One is unable to say for sure when a working system might be in place — the target is 2021 — or where in the world that might be.

The company has reviewed thousands of proposals for routes in countries including Mexico, Britain, India and the United States, and it is testing the waters with governments around the world. “We consider it a race for the first hyperloop,” Mr. Ammori said.

Hyperloop transit has it critics, who describe the idea as an ambitious pipe dream that has left many questions unanswered, including several about its cost. Some scoffed when Elon Musk, the serial tech entrepreneur, released a white paper on hyperloop technology in 2013 that claimed a link between San Francisco and Los Angeles could be completed for less than $ 6 billion. (More has been spent to renovate a single California bridge.)

Mr. Musk’s white paper was made available to the public as means of encouraging hyperloop development. His own companies, which include SpaceX and Tesla, are not formally involved in Hyperloop One’s work.